Log (BOOL)

Conditional logic in ComfyUI lives on BOOL wires - is the checkbox on, did this node decide yes or no - and you can't always tell just by looking. Log (BOOL) (LogBool) prints a boolean to the console as it passes through, so you can actually see whether that branch of your graph fired the way you think it did. It's the boolean member of the RF Nodes Log family, and it exists because "did it or didn't it" is the single most common debugging question in a graph full of toggles.

How it works

Same recipe as the pack's other Log nodes: LogToConsole(prefix, value) writes a cyan line to the terminal where ComfyUI runs, then the node returns the value unchanged. The passthrough is the important part - you don't dead-end the graph to observe it. Wire the BOOL into the Log node and out to wherever it was going.

The inputs that matter

• value - a BOOL, forceInput, so it must be wired from a node that outputs a true/false.
• prefix - the label before the value (default Value:). Something like use_controlnet: makes the line readable at a glance.

Output: BOOL - the same boolean, unchanged, passed on to the next node.

When you'd use it

Toggles and switches, mostly. A workflow that picks a different model or passes through a different branch based on a boolean - an "enhance or not" checkbox, a batch-setting that flips something on - is exactly where a silent False can send you down the wrong rabbit hole. Log the boolean at the decision point and you'll see, in the console, exactly what the graph decided and when.

One honest caveat: booleans are already pretty visible - a toggle's state is right there on the node. The Log node earns its keep when the boolean arrives from somewhere (a compare, a switch) rather than being a literal checkbox, because then the state isn't visible anywhere in the UI.

Installing RF Nodes

No dependencies, no models. Via ComfyUI Manager search "RF Nodes", or:

cd ComfyUI/custom_nodes
git clone https://github.com/foxtrot-roger/comfyui-rf-nodes

Restart ComfyUI; find it under RF in the menu.

Common issues

• "It prints True/False - where?" - In the console/terminal running ComfyUI, not the browser. Launch ComfyUI from a terminal if you want to see these.
• "I don't need this node, the toggle shows the state." - Fair. Reach for it when the boolean is computed upstream, not when it's a checkbox you set yourself.